I’m 47, and I teach 18-year-olds, so I think about this kind of question a lot. Here’s what I’ve learned when I get older:
1) Be confident in yourself. When I look back, I regret all the times I didn’t do something or gave up because I didn’t believe I could succeed at it. I once wanted to be a dancer, but I didn’t think I had a dancer’s body. Well, along came contemporary dance that celebrates all shapes. If I had believed in myself, I could have been part of that movement. I also wanted to be a writer, but I didn’t believe in the things I was writing and would lose faith in them. Now, when I read those things I see I was doing just fine and should have kept on going. Be confident in anything and everything that you do — I cannot stress this enough.
2) Drinking alcohol frequently or excessively is not a good idea. During college and graduate school, I developed a habit of partying with my friends and unknowingly wired my brain to enjoy intoxication. If I hadn’t done that, I would have saved a lot of time and money. The same goes for smoking. Be wary of mind-altering substances.
3) Use your 20s as a time to meet your life partner. You’ll be shocked at how things change once you are out of school. No longer will you be hanging out with people your age. You might get a job in an office full of married 40-year-olds. Do not put love on hold. Find a great person to share life with. Learn to accept that person’s negatives. You will NOT find someone else better later.
4) Take (and print) photos of the places you live. Not posed photos, but real pictures of the messy bedrooms and outdated kitchens you’ll wind up living in. Take pictures of your car when it’s dirty and sitting in your work parking lot. I did this, and now I love those photos of the ordinary existence that was my life.
5) Someone else who answered this question said that choices you make now would affect your entire life. True. Choose a career that has to mean. Nursing, scientific research, or environmental activism, for example. You will spend a lot of your life at work and come to understand what “the grind” is. After giving all your vitality and energy to your job, you want something back. Money goes to pay the bills, so all that’s left is the sense that you are doing something good for the world. That can’t happen in some professions, so choose carefully.
6) In a few years, your relationship with your parents will change. You will see them as people instead of authority figures. You will see their faults more clearly and see how those errors affected you. Don’t let your parents manipulate you. You owe them kindness and consideration, but not your soul.
7) Stay in touch with all your friends, even when it’s inconvenient, or they are annoying you. I regret letting certain people disappear from my life, and there have been times when I needed friends and didn’t have any because I didn’t keep the ones I had. Another thing about friendship: You don’t choose your friends. They just show up. Consider yourself lucky when one appears — they are valuable.